1) Field of the Invention
The present invention relates to a headlamp which can obtain a predetermined luminous intensity distribution pattern (e.g., a luminous intensity distribution pattern for a dipped beam) and predetermined diffusion type luminous intensity distribution pattern located on the right and left of this predetermined luminous intensity distribution pattern (e.g., cornering luminous intensity distribution pattern), respectively.
2) Description of the Related Art
As a headlamp made longitudinally compact if viewed from the front, there is known, for example, a headlamp disclosed in Japanese Patent Application Laid-Open No. 2001-176310. Although this conventional headlamp can obtain a predetermined luminous intensity distribution pattern for a dipped beam, it cannot obtain diffusion type luminous intensity distribution patterns on the right and left of this predetermined luminous intensity distribution pattern, respectively, e.g., cornering luminous intensity distribution patterns.
In addition, as a headlamp which can obtain a luminous intensity distribution pattern for a fog lamp and cornering luminous intensity distribution patterns located on the right and left of this fog lamp luminous intensity distribution pattern, respectively, there is known, for example, a headlamp disclosed in Japanese Patent Application Laid-Open No. 10-3806. However, this conventional headlamp is long sideways and not made longitudinally compact if viewed from the front. Further, since this conventional headlamp is long sideways if viewed from the front, it is possible to obtain cornering luminous intensity distribution patterns diffused right and left relatively easily but it is relatively difficult to obtain a luminous intensity distribution pattern diffused downward.
It is an object of this invention to provide a headlamp which can be made longitudinally compact if viewed from the front and which can obtain a luminous intensity distribution pattern diffused downward by being made longitudinally compact if viewed from the front.
According to one aspect of this invention, in order to achieve the above object, there is provided a headlamp which comprises: a main reflector which has a light axis, sub-reflectors built on left and right of this main reflector, respectively, and a light source which is arranged on the light axis. The main reflector has a longitudinal structure which has such a width near the light axis as to be able to obtain a highest light intensity and such a height as to be able to obtain the predetermined luminous intensity distribution pattern, if viewed from the front. The sub-reflectors have vertical wall structures which obtain predetermined diffusion type luminous intensity distribution patterns on the left and right of the predetermined luminous intensity distribution pattern, respectively.
As a result, according to the above aspect, if the light source is turned on, the light from the light source is reflected by the main reflector and the predetermined luminous intensity distribution pattern having the highest light intensity is obtained. In addition, the light from the light source is reflected by the sub-reflectors and the predetermined diffusion type luminous intensity distribution patterns are obtained on the left and right of the predetermined luminous intensity distribution patter, respectively.
As can be seen, according to the above aspect, since the sub-reflectors are built on the left and right of the longitudinal main reflector, respectively, the headlamp can be made compact longitudinally if viewed from the front. In addition, according to this aspect, by making the headlamp compact longitudinally if viewed from the front, the sub-reflectors are provided longitudinally, i.e., provided to be elongated vertically and luminous intensity distribution patterns diffused downward are, therefore, obtained.
These and other objects, features and advantages of the present invention are specifically set forth in or will become apparent from the following detailed descriptions of the invention when read in conjunction with the accompanying drawings.